Electric switch



Feb. 23 ,192e. 1,574,533

C. D. AINSWORTH ELECTRIC SWITCH Filed Feb. 9. 1922 2 Sh ts-Sheet 1 agr-In veniar, M b .M

Feb. 23 1926. 1,574,533

c. D. AINSWORTH ELECTRIC SWITCH Filed Feb. 9, 1922 2 Sheets-Sheet 2 lJivven'or.

Patented Feb. 23, 1926.

UNITED STATES PATENT OFFICE.

CHESTER D. AINSWORTH, OF WOLLASTON, MASSACHUSETTS, ASSIGNOR, BY MESNE.AS-

SIGNMENTS, T0 CONDIT ELECTRICAL MANUFACTURING CORPORATION, OF BOS- TON,MASSACHUSETTS, .A CORPORATION OF MASSACHUSETTS.

ELECTRIC SWITCH.

Application filed February 9, 1922. Serial No. 535,220.

To aZZ whom it may concern:-

Be it known that I, CHESTER D. AINswon'rii, a citizen of the UnitedStates, residing at Wollaston, in the county of Norfolk and \State ofMassachusetts have invented in Impro ement in Electric Switches, f whichthe llowing is a specification.

This invention relates to oil immersed electric switches.

Due to the electro-magnetic stresses act- I ing upon the conductingcomponents of an electric switch by current of a relatively high value,-under certain conditions, the relatively movable conducting componentsmay be forced away from firm electrical contact with each other andarcing may take place therebetween, and, consequently, the capacity ofthe switch may be reduced.

An object of this invention is to provide an electric switch with animproved form and arrangement of movable and stationary switch membersand especially movable and stationary contact or arcing members by whichthe magnetic eflect of the current carried by them acts to improve theelectrical engagement of the co-acting contact members.

A further object is generally to improve the operation and constructionof an electric switch.

Certain features of this invention are disclosed in my co-pendingapplicationsSerial No. 522,228, filed December 14, 1921, Serial No.522,227, filed December 14, 1921, and Serial No. 585,672, filedSeptember 1, 1922.

Fig. 1 is a side elevation of a switch embodying m invention with theside wall of the casing roken away to show the stationary and movableswitch members.

Fig. 2 is a longitudinal sectional detail, in elevation, of the switchof Fig. 1 illustrating the switch-open position of the switch members.

Fig. 3 is a plan detail of the movable switch member.

Fig. 4 is a sectional view of the movable switch member along line 4-4of Fig. 3.

Fig. 5 is a side view of the auxiliary contact members in switch-openposition.

Fig. 6 is a similar view of the auxiliary contact members in switchclosed position.

I have herein illustratedmy invention as incorporated in an oil immersedelectric switch of the up-break type; yet the invention is not limitedto such a type of switch.

As here shown, the electric switch includes a casing comprising the oilreceptacle 10 and the switch frame 11. Said switch frame comprises acover for the oil receptacle and is secured to the top of saidreceptacle by suitable means as the bolts 12. Stationary switch members13 are carried by said switch frame and depend into the oil in thereceptacle. The movable switch member has its switch rod 14 pivotallysecured to and dependent from the pivoted arm 15 of the switch operatingmechanism. Said mechanism is contained within the switch frame andincludes an operating shaft 16 which is journalled in and extendsthrough the opposite side walls of the switch frame. An arm 17 issecured to an outer end of said shaft externally of the casing and isconnected by means of the rod 18 to the electrically controlledswitchactuating mechanism 19 secured externally to the switch frame. Aspring 20 is in engagement with the arm 17 of the operating mechanismand serves to raise the movable switch member to switch-open positionand is adapted to be compressed by the switchactuating m echanism 19 inmoving the movable swite member to switch-closed position. Stationaryswitch members 13 are carried by said switch frame 11 and terminate,within the casing, in the inwardly directed contact plates 21, the upperfaces of which are adapted to be engaged by the bridging or brush memberof the movable switch member in theusilal manner.

My invention resides more particularly in the construction andarrangement of the auxiliary contact or arcing members by which thecircuit through the switch is finally interrupted. The stationaryauxiliary contact member structure includes supporting members 22 whichare secured removably, as by the bolts 22, to the under side of thecontact plates 21 and connected electrically therewith. Said supportingmembers extend laterally on opposite sides of said contactplates and theextended ends members comprise the substantially inflexible plates 23which are secured removably by suitable means, as the bolts 24:, to t ereflexed ends of said supporting members; and said contact membersextendupwardly and inwardly and terminate a substantial distance aboveand to the opposite sides of said contact plates 21. The upper ends 23of said plates are reflexed inwardly to form cured to the lower-face ofachannel member 26 having the lateral upstanding ears 27.

i The lower end of. the switch rod 14: is disposed between said ears anda pivot pin 28 is passed through said switch rod and ears whereby toconnect the brush member pivotally with the switch rod. The brush memberis adapted to engage the upper faces,-

of the stationary contact plates 21 andcarry the current in the usualmanner.

The movable auxiliary contact structure includes the supporting members30 which are secured to the outer faces of said upstanding ears 27. .Theintermediate ortions 30 of said members on opposite sldes of the ears 27of the channel member 26 arereflexed outwardly and are then againreflexed to provide end portions 30 which are disposed in parallelrelation with each other.

Movable auxiliary. contact members including the downwardly extendedresilient strips 31 are secured by suitable means as the bolts 32 to theend-portions 30 of eaid supporting members 30. Contact or arcing members33 are secured removably by'suitable means as the bolts 34 to the lowerends, of said flexible strips 31. Bracing members 36 are extendedbetween the pairs of contact members on opposite sides of the brushmember and are secured to the ends 30 of the supporting members 30 bythe bolts 32. Tie-members 35 are extended between the contact memberson'the same side ofthe brush member and are also secured 'to saidcontact member 30 by the bolts 32.

This arrangement provides a rigid and strong supporting structure bywhich the movable contact members 31 are secured rigidly and connectedelectrically. It will be noted that all members of the supportingstructure are arranged edgewise with regard to the direction of motionof the movable switch member whereby but a small surface is presented tothe oil to oppose the movement of the movable switch member andconsequently the switch member may move rapidly into open position.

The arrangement of the stationary auxiliary contact members 23 and themovable auxiliary contact members 31 is such that the movable contactmembers engage the stationary contact members at the tips 23 thereof andupon a continued movement of the movable switch toward switch closedposition, the movable contact members 31 are flexed outwardly whilebeing moved downwardly along and in contact with the outer face of saidstationary contact members 23 whereby a long wiping action and goodelectrical contact is obtained. The stationary contact members extend asubstantial distance above the stationary contact plates 21 of thestationary switch members so that the movable switch member may beaccelerated and have a rapid motion when the auxiliary movable andstationary contact members finally separate and as a result, the arcwill be rapidly drawn out and quenched.

At that part of the movement of the switch wherein the stationary andmovable contact members are in engagement but the brush members are freefrom engagement 7 with the stationary switch members, the currentbetween the switch members will be divided into two parallel pathsincluding the auxiliary contact members on both sides of the switchmembers and this arrangement constitutes an important part of theinvention.

By reason of the parallel arrangement of the auxiliary contact membersabove set forth and the parallel division of current in said contactmembers, with the current flow ing in the same direction in adjacentcontact members, the magnetic effect of the parallel currents is such asto inter-react and tend to draw the movable resilient contact members 31inwardly toward each other and thereby into increased firm and securecontact with the co-acting stationary auxiliary contact members wherebyto insure good electrical engagement between the auxiliary stationaryand movable contact members regardless of the value of the currentcarried by them.

The arrangement of the auxiliary contact members at the sides of thestationary switch members is also advantageous in that gas can risefreely from the contact members and oil can flow freely about thecontact.

members without substantial obstruction whereby to facilitate thequenching of the arc and the cooling of the auxiliary contact members.

It is obvious that the invention may be embodied in modified structureswithout departing from the spirit thereof.

I claim:

1. An electric switch having two relatively movable switch members eachformed with a main current-carrying member and the engagement of theirrespective .main

current-carrying members and arcing mem-.

bers.

2. An electric switch having two relatively movable switch members eachformed with a main current-carrying member and two arcing membersdisposed on opposite sides of and extended in a circuit-openingdirection beyond the contact face of and electrically connected withsaid main current-carrying member, and said switch members arranged tobe moved to cause the engagement of their respective maincurrent-carrying member and arcing members, and means to pass thecurrent in the same direction through thearcing members of the switchmembers.

3. An electric switch having a main current-carrying member, and tworelatively flexible arcing members secured to and disposed on oppositesides of said main current-carrying member, and a movable switch memberincluding a bridging-member arranged to engage said main currentcarryingmember, and two electricallymovable there ith into engagement withconnected. rcing members disposed on opposite sides f said bridgingmember and the aforesaid fl xible arcing members.

4. In an electric switch,. an auxiliary stationary and a cooperatingauxiliary movable-contact member, both arranged substantially in line,and said movable con- -tact member arranged to engage said stationarycontact member substantially at-the upper end thereof and move from theupper end toward the other end while in engagement with the face thereofand while preserving substantially its initial area of contact with saidstationary contact member and have a final engagement with saidstationary contact member a substantial distance away from theiupper endthereof and with substantially itst initial area of contact therewithand a m in contact member associated with and disposed remote from thefree end of each auxiliary contact member.

5. In an electric switch, a movable switchmember comprising a'supportingstructure, four arcing members arranged in sets of two at the oppositeends of said supporting structure, and a main bridging member carried bysaid supporting str cture and having its opposite contact-eni'. disposedbetween the arcing members of he opposed sets.

G. Inan electric switch, a movable switchportions inwardly above and onopposite sides of member comprising a supporting structure, four arcingmembers all connected in parallel and arranged in sets of two at theopposite ends of said supporting structure, and a main bridging'membercarried by said supporting structure and having its oppositecontact-ends disposed between the arcing members of the opposed sets.

7. In an electric switch, a switch member including a contact plate, a.supporting member secured to said plate having lateral downwardly andoutwardly directed opposed end-portions extended on opposite sides ofsaid contact plate, and contact members secured to said end-portions andextended upwardly and inwardly above said contact plate.

8. In an electric switch, a stationary switch member including a contactplate, a supporting membensecuredto said plate having lateral downwardlyand outwardly directed endortions extended on opposite sides of saicontact plate, and contact members comprising flat strips secured tosaid end-portions and extended upwardly andinwardly above and onopposite sides of the contact face of said contact plate.

9. In an electric switch, a stationary switch member including a contactplate, a supporting member secured to said plate having lateraldownwardly and outwardly directed end-portions extended on oppositesides of said. contact plate, and contact members com rising fiat stripssecured removably at t eir lower ends to said endand extended upwardlyand the contact face of said contact plate.

10. In an electric switch, a stationary switch member having a maincontact face and two detachable auxiliary contact members disposed onopposite sides of and angularly inclined with respect to said maincontact face, and a movableswitch member having a main contact memberarranged to engage said main contact face, and two detachable. auxiliarycontact members disposed on opposite sides of said main contact memberarranged to engage the auxiliary contact members of said stationaryswitch member.

11. In an'electric'oil switch, a movable switch member comprising aswitch rod, a supporting structure secured thereto comprising aplurality of spaced flat members arranged with their edges directed inthe path of movement of said switch member auxiliary contact memberscarried by said supporting structure and a main currentcarrying memberdisposed between said spaced fiat members.

12. An electric switch having a movable switch member comprising asupporting structure, a bridging member disposed within the ends of saidsupporting structure and extended lengthwise thereof, and twoelectrically-connected arcing members carried by each end of saidsupporting structure on opposite sides of and extended beyond the endsof said bridging member. v

13. An electric switch having a movable switch member comprising asupporting rod, a supporting structure connected with the lower end ofsaid rod, said supporting structure including two substantially paralleland spaced bars extended laterally in'both directions from said rod, andtwo arcing members extended in the direction of movement of the switchmember and secured in spaced relation at each end of said supportingstructure.

Y 14. An electric switch having a movable switch member comprising asupporting rod, a supporting structure connected with the lower end ofsaid rod, said supporting structure including two substantially paralleland spaced bars extended laterally in both directions from said rod, andtwo arcing members extended in the'direction of movement of the switchmember and secured in spaced relation at each end of said supportingstruc ture and a main bridging member carried by said structure betweensaid contact *members.

15. An electric switch having a movable switch member including arectangular supporting frame comprising spaced side plates, endconnecting and separating plates, arcing members depending from thecorners of said frame, and a bridging member disposed within said frameand arcing members.

plates, and a main bridging member carried by said frame between saidarcing members.

17. An electric switch having a movable switch member including arectangular frame comprising connected and spaced end and side plates,arcing members carried by the connections between said end and sideplates, supporting plates extended within said frame from the cornersthereof, and a switch rod securedto said supporting plates.

18. An electric switch having a movable switch member including arectangular frame comprising connected and spaced end and side plates,arcing members carried by the connections between said end and sideplates, supporting plates extended within said frame from the cornersthereof, a switch rod secured to said supporting plates and a mainbridging member carried by said supporting plates and disposed withinsaid areing members.

In testimony whereof, I have signed my name to this specification.

CHESTER D. AINSVVORTH.

